1. Technical Field
The disclosure relates to an imaging apparatus that irradiates a subject with excitation light or visible light and receives reflected light from the subject by a plurality of pixels to perform photoelectric conversion, to thereby output image information.
2. Related Art
Conventionally, in medical fields, an endoscope system is used for observing an interior of an organ of a subject. In general, the endoscope system, which is a kind of an imaging apparatus, inserts an elongated and flexible insertion section into a body cavity of a subject such as a patient, and irradiates body tissues in the body cavity with white light through the inserted insertion section and receives reflected light by an imaging unit provided at a distal end of the insertion section, to thereby capture an in-vivo image. An image signal of the biological image taken by the endoscope system is transmitted to an image processing device outside the subject body through a transmission cable inside the insertion section and subjected to image processing in the image processing device and is, thereby, displayed on a monitor of the endoscope system. A user such as a doctor observes the interior of the organ of the subject through the in-vivo image displayed on the monitor.
As such an endoscope system, there is known technology capable of performing fluorescence observation that irradiates body tissues into which a fluorescence agent including a fluorescence marker is introduced with excitation light of a specific wavelength to capture fluorescence light or normal observation that irradiates body tissues with normal light in a visible wavelength range to capture reflected light (see Japanese Laid-open Patent Publication No. 2006-61435). In this technology, a brightness level of a fluorescence image is automatically adjusted with a brightness level of an image captured using the normal light set as a target value, whereby it is possible to display the fluorescence image with proper brightness without imposing burden on a user.